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Tech + EngineeringTech & Engineering

Snowden-Designed Device Prevents Your iPhone From Revealing Compromising Data

ByJulia DavisNOVA NextNOVA Next

If there’s anyone who has a right to be paranoid about phone security, it’s Edward Snowden. For the past three years, Snowden has been living in Russia on asylum after leaking classified NSA documents that revealed numerous federal surveillance programs. But Snowden is determined to continue advocating for secure communication from abroad.

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Today, Snowden and well-known hardware hacker Andrew “Bunnie” Huang plan to present designs for a device that wires into iPhones, securing their internal hardware so that electrical signals like radio waves cannot be hijacked to transmit users’ locations to outside parties.

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iPhone Design
The orange highlighted part is a proposed flexible printed circuit which exits via the SIM card port and routes signals from the modified iPhone6 mainboard to the introspection engine’s electronics.

Snowden approached Huang with the idea near the end of 2015, and although the two have never actually met face-to-face, they have been working on this “introspection engine” since then, and released a detailed paper on the concept today before presenting their designs at the MIT Media Lab.

The team hopes that this technology will have the capabilities to protect smartphones owners abroad who need to shield their phones from government-funded opponents with high-tech hacking and surveillance capabilities, such as journalists working abroad.

Huang and Snowden’s solution is an add-on that upon first glance looks like nothing more than the average external battery case. However, unlike a case, it would have wiring that runs into the smartphone’s internal hardware.

Here’s Andy Greenberg, reporting for Wired:

It would function as a kind of miniature, form-fitting oscilloscope: Tiny probe wires from that external device would snake into the iPhone’s innards through its SIM-card slot to attach to test points on the phone’s circuit board. (The SIM card itself would be moved to the case to offer that entry point.)

Those wires would read the electrical signals to the two antennas in the phone that are used by its radios, including GPS, Bluetooth, Wi-Fi and cellular modem. And by identifying the signals that transmit those different forms of radio information, the modified phone would warn you with alert messages or an audible alarm if its radios transmit anything when they’re meant to be off. Huang says it could possibly even flip a “kill switch” to turn off the phone automatically.

Many users turn on the “airplane mode” setting in order to make sure their phone’s radio signal is off. However, it has been shown that airplane mode can be hacked to make it so the phone’s signal is still detectable to those who are want it. However, hardware-related signals are almost impossible to hack into, which means with this technology, users will have a “bet-your-life assurance,” as Huang put it, that the phone’s radios are not being tampered with.

This kind of security is extremely important for reporters in nations where the government could take advantage of a target such as a smartphone and compromise journalists’ location. Tools such as smartphones have become tools of the trade in modern day journalism, but in some circumstances they are now making journalists vulnerable. Snowden and Huang say they developed the idea specifically to protect journalists, citing Marie Colvin’s story as a case study in their paper. Colvin, an American war correspondent, was tracked by the Syrian government based on her cellular communication, and killed in a targeted bombing after reporting on civilian casualties.

There have been other attempts to block all radio signals in a smartphone, like the obvious solution of simply switching your iPhone off with its power button. But Snowden warned in a 2014 NBC interview that that isn’t always a sure bet thanks to clever malware that makes it look like your phone is switched off when it’s not. And Faraday bags are designed to block all radio signals, but can still leak radio information is some instances, according to Huang.

The goal of this is to allow reporters to use their functions like audio and video recording without worrying about the radio signals being hacked. In a talk to the MIT Media Lab via video stream, Snowden also added that this modification could be used to detect stealthy attacks on phones, and expose governments’ hidden intentions when it comes to spying on the media.

At the moment, the iPhone modification is still in the design stage, but Snowden and Huang have successfully tested their method of picking up electrical signals to make sure that it can differentiate and spot radio signals. They hope to develop a prototype over the next year.

Concept Design
Conceptual rendering of a battery case style introspection engine, piggybacked on an iPhone 6.

Photo credit: PubPub/CC BY 4.0

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